660 



J. T. PATTERSON 



Em N 



D C 



Tr Ep 



Fig. 32 A portion of the left side of the section shown in figure 51. X 306. 



Fig. 33 A similar region from the section shown in figure 58. D.C., cells in 

 mitosis; G.C., giant cell, which is frequently found at the base of the blastocyst 

 At mis the beginning of a mass of Trager cells which later extends up to receive the 

 entoderm. X 306. 



Fig. 34 A portion of the left side of the section shown in figure 60. The mass 

 at m now carries the entoderm, while the outer layer of Trager cells is seen as the 

 basal fragment (&./.). Note that the vacuoles are beginning to appear in the 

 syncytium. X 319. 



Fig. 35 A portion of the right side of a section from specimen No. 175, 

 plate 8. The Trager epithelium (Tr.Ep.) is quite well organized, and root-like 

 growths of Trager tissue are seen extending into the mucosa at Em. X 485. 



